Dual mono or stereo bass amp

I am not aware of any bass amps that meets your needs. I have a couple of bass amps in my collection that have dual power amps but all of them have mono preamps. Unfortunately, if you really want to run Ric-O-Sound, I believe you will either need to build a rack rig or run two separate amps.

I used to tour with an Ashley MX508 rack mixer and a QSC power amp. I used Shure A95U line matching transformer to plug my basses into the mic inputs. With this setup the mic/line switches on the channels acted like mute switches. This sort of rack setup can be dialed in to run stereo.

 

a stereo power amp with a separate pre-amp for each channel would do what you ask.

 

The Alembic F-2B is a stereo one space rackmount tube pre-amp. You can output each channel to its own side of a stereo power amp or output both channels in mono. The preamp is great for vintage tones and is based on a Dual Showman so it has the Fender-type tone circuit. No built in DI. Acoustic Image may still sell some amps with two discrete channels.

 

Acoustic Image does still have amps with two channels, but they only have one power section, so you would need an additional power amp in order to have each channel going to its own speakers. Would be easier (and less expensive) just to get something like two Quilters to drive your two cabinets separately.

 

Fendwr Twin... use both channels

 

The channels of a Twin are out of phase with each other.

 

Are all Fender amps like this?

 

Two thoughts...
-I run my 4001 into both channels of a mid 1970s mono 200w valve amp and it works for me.
-With two separate amps the one taking the signal for the bridge pickup could be less than 200w (and perhaps lighter) if you have the .0047 cap in place to reduce low end.

 

No, it depends if it has Vibrato and how the Vibrato is implemented. The Twin has an extra gain stage in the Vibrato channel which flips the polarity.


IMHO it doesn't really matter anyway because this type of amp has two preamps, but only one output section; and the OP is looking for full dual mono/stereo.

 

The Concert amp I had (made in 1962) was that way, too.

As to a stereo bass amp, does Walter Woods still make his? I used to have a single power amp version.

 

The blackface AB763 Showman has both channels in phase. I believe this applies to all AB763 circuits that lack Reverb to include: "Deluxe, Vibrolux, Tremolux, Pro, Concert, Showman and Band-Master". Ref AB763 Models


Reverb models have extra tubes. The reverb driver is made up of both triodes of a 12AT7. The Reverb return is through one triode of a 7025/12AX7. The extra triode from the 7025/12AX7 is used as an additional gain stage in the Vibrato channel. The extra triode is why the polarity is inverted between the two channels.

 

My Concert Amp was the 6G12-A version.